Use 12mm x 1.25mm for Rad Power Bikes and Mahle/EBIKEMOTION Equipped E-Bikes. Use 10mm x 1.0mm for Rohloff, Enviolo, Shimano Nexave, SRAM I-Motion, and SRAM Torpedo. Use 3/8-26 for Shimano Nexus, Shimano Alfine, Shimano Coasting. If your bike does not have upper eyelets for the extenders you will want to get our Mounting Pucks for Road and Gravel Forks or Mounting Pucks for Suspension Forks and Rear Triangles.